Bug 814907 - Fix test_interfaces.html failures. r=orange

dom/tests/mochitest/general/test_interfaces.html

@@ -526,7 +526,9 @@ var interfaceNamesInGlobalScope =
     "RTCSessionDescription",
     "RTCIceCandidate",
     "RTCPeerConnection",
-    "LocalMediaStream"
+    "LocalMediaStream",
+    "CSSConditionRule",
+    "CSSGroupingRule"
   ]
 
 for (var i in SpecialPowers.Components.interfaces) {